| BOM papermaking felt is a kind of industrial, especially used in paper making, whichbelongs to the precious consumable materials. It is equivalent to the "conveyor belt", playinga role in supporting, transferring and dewatering. Fibers, filler materials and others willadhere to the papermaking felts, which results in clogging the felts and pollution. Therefore,due to the problems of short life-time resulting from pollution, in this thesis, BOMpapermaking felts would be finished with fluorine-containing finishing liquid that has thecharacteristics of water and oil repellent. Since fluorine-containing finishing liquid hasexcellent performance of compounding, and effect on BOM papermaking felts caused by onlyone kind of fluorine-containing finishing liquid is not excellent, two kinds of differentfluorine-containing finishing liquid were chosen to be compounded to develop a newfluorine-containing finishing liquid which was more suitable and had more excellentcharacteristics of anti-pollution performance. And the papermaking felts were finished with itby dip-molding.In the thesis, the process parameters of heat-setting that affect the compression elasticity,water resistance, abrasion resistance and other performance of BOM papermaking felts wereanalyzed by single and orthogonal experiment. The raw material of BOM papermaking feltswas nylon66.Combined with the fuzzy mathematics, the actual process parameters werefinally determined. The results showed that the compression elasticity and abrasion resistanceof heat-treated samples were improved, however, the water resistance of the heat-treatedsamples was improved. After comprehensively evaluating the performance of heat-settedsamples, the optimum process applied to BOM in the experiment was as following: the besttemperature was set at240oC, time was at positive60s negative30s, and moisture content ofBOM was set at30%.In the thesis, firstly, polyvinylidene fluoride (PVDF) emulsion with differentconcentration were prepared and were used to finish BOM papermaking felts by dip-molding.The concentration of PVDF emulsion that affects the anti-pollution performance,water resistance and abrasion resistance was analyzed. According to the comprehensiveanalysis, the concentration of PVDF emulsion was determined at20g/L. Then, based on thisresults, different concentrations of adhesive (component was epoxy resin) was added to PVDFemulsion to prepare the composite emulsion which was used to finish BOM papermakingfelts in the same way. The concentration of adhesive that affect the performance of BOMpapermaking felts was analyzed. The results showed that anti-pollution performance ofPVDF/adhesive-finished samples was better than that of PVDF-finished samples. When theconcentration of PVDF and adhesive was20g/L and8g/L, the amount of contamination offinished samples was1.35g, the contamination rate was58.84%, the soapingdecontamination rate was97.68%, and the contact angle value was139.2°. However,changes of water resistance and abrasion resistance were not obvious, which has little impacton its actual use.In the thesis, in order to develop an excellent anti-pollution finishing liquid, another fluorine finishing agent——polytetrafluoroethylene (PTFE) dispersion liquid was chosen tocompound with PVDF/adhesive system (the concentration of PVDF/adhesive was20g/L and8g/L).Different concentrations of PTFE were added to study the concentration that affect theperformance of BOM papermaking felts and determine the best anti-pollution finishingliquid formula through the analysis. The results showed that inthe PVDF/adhesive/PTFE system, when the concentration of PVDF,adhesive and PTFEwas20g/L,8g/L and6g/L, the amount of contamination of finished samples was1.04g, thecontamination rate was32.75%, the soaping decontamination rate was98.85%, and thecontact angle value was142.7°. Compared with PVDF/adhesive system, the anti-pollutionperformance and water resistance was improved. After testing, compared with the results offluorine compound finishing liquid, the results of PVDF or PTFE were worse. Therefore, inthe new PVDF/adhesive/PTFE finishing liquid, the concentration of PVDF, adhesive andPTFE was20g/L,8g/L, and6g/L respectively. |
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